Paint mask structure



Nov. 28, 1944. DUGGAN V 2,363,843

PAINT MASK STRUCTURE Filed'May 1s, 1 942 FIG.2

INVENTOR. JAME S EDWARD DUGGAN Patented Nov. 1944 UNITED STATES PATENTOFFICE a 2,363,843

PAINT MASKV STRUCTURE James Edward Duggan, Detroit, Mich. ApplicationMay s, lsiaseriai No.44a51s 3 Claims: ('Cl.'91-65) This invention,relates generally to devices;

that are used during painting or plating opera tions to protect portionsof articles from paint or plating material applied to adjacent portionsthereof, and refers more particularly to masks for preventing paint orplating material from contacting or passing onto theteeth of gears,pinions, splines and the like when other portions of the gears, etc.,Such as the body portions thereof, are painted or plated.

One of the essential objects of the invention is to provide a maskcapable of thoroughly protecting the teeth mentioned without in any wayinterfering with the painting or plating opera, tion.

Another object is to provide a mask that may be quickly and easilyapplied to and removed from the portions to be protected without marringor impairing any part thereof. a 4

Another object is to provide a mask that is simple in constructionandeconomical to manufacture.

Other objects, advantages and novel details of construction of thisinvention will be made more apparent as this description proceeds,especially when considered in connection with the accompanying drawing,wherein:

Figure 1 is a fragmentary side elevation of a gear with a mask embodyingmy invention applied thereto and having partsbroken away and in section;

Figure 2 is a fragmentaryedge elevation of the gear illustrated inFigure 1 and showing in section the mask applied thereto; a

Figure 3 is a fragmentary side elevation of a gear. and a slightlymodified form of mask em-.

bodying my invention applied thereto;

Figure 4 is a sectional view taken on line 4-4 of Figure 3.

In Figures 1 and 2 I have illustrated an assembly wherein an annularbody 2|] of a mask B" has internal teeth or projections 2| forpreventing the paint. or plating material from entering the plied to'the gear A by causing the teeth 2| of the mask to enter the spaces 22between and mesh with the teeth 23 of the gear A to assume the maskingposition illustrated in Figure 1.

When in this position an external metal ring (not shown) provided withcontracting means such as an adjusting screw, may be applied to theoutersurface 25 of thebody 20 of the mask to cause the teeth 2| of the maskto be pressed inwardly into ,snug engagement withtheexternal teeth 23 ofthe gear A to be protected. However, the mask B is preferably undersizedrelative to the gear A so that the rubber or rubber. composition fromwhich the mask B is formed has to be stretched, slightly when the maskis applied asaforesaid to the gear. Thus, when the mask B is in itsmasking position as illustrated in Figure 3, the inherent resiliencythereof alone should normally be sufficient to cause the teeth H of themask to snugly engage the teeth 230i the gear to keep paint or platingmaterial off the working surfaces of thegteeth 23.0f the gear.

mask 13 may be applied to the gear A by causing the teeth 3| of the maskto enter the spaces 33 between and mesh with the teeth 30 of the gear toassume the masking position illustrated in Figure 3. When in. thispositionan. internal,

metal ring (not shown) provided with expanding means such as anadjusting screw, maybe applied to the inner surface 34 of the body 35 ofthe mask to cause the teeth 3| of the mask to be pressed outwardly intosnug engagement with the internal teeth 30 'of the gear to be protected.However, the mask B is preferably oversized relative to the gear A sothat the rubber or rubber composition from which the mask is formed hasto be squeezed or contracted slightly when the mask is applied asaforesaid to the gear. Thus, when the mask B is in its masking positionas illustrated in Figure 3, the inherent resiliency thereof alone shouldnormally be sufficient to cause the teeth 3| of the mask to snuglyengage the teeth 30 of the gear to keep paint or plating material offthe working surfaces of the teeth 30 of the gear.

Thus, in each instance, the masks are formed of resilient material suchas rubber, or rubber composition and will yieldably engage the teeth ofthe gears or the splines as the case may be.

Such masks may be easily applied to or removed from the gears or splinedportion and will efl'ectively keep paint or plating material off theworking surfaces of the teeth or splines thereof. In each instance themasking engagement between the masking elementand teeth of the articleis such that the masking element effectively prevents paint or platingmaterial applied to the body portion of the article from entering thespaces between the teeth of said article. Also in each instance themasks are under tension relative to the portion of the article to beprotected whereby snug, tight, non-slip, glove-like fit is obtainedbetween the masking element and article to maintain the maskingengagement aforesaid.

What I claim as my invention is:

1. Means for protecting the working surfaces having an interiorperipheral surface substantially less than the exterior peripheralsurface of said gear so that said masking annulus may be fitted bystretching it under tension over the Working surfaces to be masked, saidmasking annulus being substantially equal in width to the width of thegear and having portions so spaced and of such depth and thickness thatwhen the masking annulus is stretched over the working surfaces to bemasked said portions will be squeezed into snug non-slip surface tosurface engagement with the working surfaces of said teeth to preventpaint or plating material applied to the spaces of cireumferentiallyspaced transversely extendof circumferentially spaced radial teeth of agear from paint or plating m'aterialvapplied to the body portion of saidgear, comprising a resilient relatively elastic one piece solid maskingannulus having an interior peripheral surface substantially less thanthe exterior peripheral surface of said gear so that said maskingannulus may be fitted by stretching it under tension over the workingsurfaces tobe masked, said masking annulus having radial projections sospaced and of such depth and thickness that when the masking annulus isstretched over the working surfaces ing teeth of a gear from paint .orplating material applied to the body portion of said gear, comprising arelatively elastic solid masking annulus for peripheral matingengagement with said gear, said masking annulus having a peripheralsurface substantially less than the mating peripheral surface of saidgear so that saidmasking'annulus may be fitted by stretching it undertension against the working surfaces to be masked,said masking annulushaving transversely extending portions substantially equal in length tothe length of the transversely extending teeth of said gear, thetransversely extending portions being so spaced and of such depth andthickness that when the masking annulus is stretched over theworkingvsurfaces to be masked said transversely extending portions willbe squeezed into snug nonslip Surfaceto surface engagement with theworking surfaces of said teeth to prevent paint or plating materialapplied to the body of the gear from entering the spaces between theteethof said gear.

JALAES EDWARD DUGGAN.

